1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef _BTRFS_CTREE_H_ 3 #define _BTRFS_CTREE_H_ 4 5 #include <linux/btrfs.h> 6 #include <linux/types.h> 7 #ifdef __KERNEL__ 8 #include <linux/stddef.h> 9 #else 10 #include <stddef.h> 11 #endif 12 13 /* 14 * This header contains the structure definitions and constants used 15 * by file system objects that can be retrieved using 16 * the BTRFS_IOC_SEARCH_TREE ioctl. That means basically anything that 17 * is needed to describe a leaf node's key or item contents. 18 */ 19 20 /* holds pointers to all of the tree roots */ 21 #define BTRFS_ROOT_TREE_OBJECTID 1ULL 22 23 /* stores information about which extents are in use, and reference counts */ 24 #define BTRFS_EXTENT_TREE_OBJECTID 2ULL 25 26 /* 27 * chunk tree stores translations from logical -> physical block numbering 28 * the super block points to the chunk tree 29 */ 30 #define BTRFS_CHUNK_TREE_OBJECTID 3ULL 31 32 /* 33 * stores information about which areas of a given device are in use. 34 * one per device. The tree of tree roots points to the device tree 35 */ 36 #define BTRFS_DEV_TREE_OBJECTID 4ULL 37 38 /* one per subvolume, storing files and directories */ 39 #define BTRFS_FS_TREE_OBJECTID 5ULL 40 41 /* directory objectid inside the root tree */ 42 #define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL 43 44 /* holds checksums of all the data extents */ 45 #define BTRFS_CSUM_TREE_OBJECTID 7ULL 46 47 /* holds quota configuration and tracking */ 48 #define BTRFS_QUOTA_TREE_OBJECTID 8ULL 49 50 /* for storing items that use the BTRFS_UUID_KEY* types */ 51 #define BTRFS_UUID_TREE_OBJECTID 9ULL 52 53 /* tracks free space in block groups. */ 54 #define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL 55 56 /* Holds the block group items for extent tree v2. */ 57 #define BTRFS_BLOCK_GROUP_TREE_OBJECTID 11ULL 58 59 /* device stats in the device tree */ 60 #define BTRFS_DEV_STATS_OBJECTID 0ULL 61 62 /* for storing balance parameters in the root tree */ 63 #define BTRFS_BALANCE_OBJECTID -4ULL 64 65 /* orphan objectid for tracking unlinked/truncated files */ 66 #define BTRFS_ORPHAN_OBJECTID -5ULL 67 68 /* does write ahead logging to speed up fsyncs */ 69 #define BTRFS_TREE_LOG_OBJECTID -6ULL 70 #define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL 71 72 /* for space balancing */ 73 #define BTRFS_TREE_RELOC_OBJECTID -8ULL 74 #define BTRFS_DATA_RELOC_TREE_OBJECTID -9ULL 75 76 /* 77 * extent checksums all have this objectid 78 * this allows them to share the logging tree 79 * for fsyncs 80 */ 81 #define BTRFS_EXTENT_CSUM_OBJECTID -10ULL 82 83 /* For storing free space cache */ 84 #define BTRFS_FREE_SPACE_OBJECTID -11ULL 85 86 /* 87 * The inode number assigned to the special inode for storing 88 * free ino cache 89 */ 90 #define BTRFS_FREE_INO_OBJECTID -12ULL 91 92 /* dummy objectid represents multiple objectids */ 93 #define BTRFS_MULTIPLE_OBJECTIDS -255ULL 94 95 /* 96 * All files have objectids in this range. 97 */ 98 #define BTRFS_FIRST_FREE_OBJECTID 256ULL 99 #define BTRFS_LAST_FREE_OBJECTID -256ULL 100 #define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL 101 102 103 /* 104 * the device items go into the chunk tree. The key is in the form 105 * [ 1 BTRFS_DEV_ITEM_KEY device_id ] 106 */ 107 #define BTRFS_DEV_ITEMS_OBJECTID 1ULL 108 109 #define BTRFS_BTREE_INODE_OBJECTID 1 110 111 #define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2 112 113 #define BTRFS_DEV_REPLACE_DEVID 0ULL 114 115 /* 116 * inode items have the data typically returned from stat and store other 117 * info about object characteristics. There is one for every file and dir in 118 * the FS 119 */ 120 #define BTRFS_INODE_ITEM_KEY 1 121 #define BTRFS_INODE_REF_KEY 12 122 #define BTRFS_INODE_EXTREF_KEY 13 123 #define BTRFS_XATTR_ITEM_KEY 24 124 125 /* 126 * fs verity items are stored under two different key types on disk. 127 * The descriptor items: 128 * [ inode objectid, BTRFS_VERITY_DESC_ITEM_KEY, offset ] 129 * 130 * At offset 0, we store a btrfs_verity_descriptor_item which tracks the size 131 * of the descriptor item and some extra data for encryption. 132 * Starting at offset 1, these hold the generic fs verity descriptor. The 133 * latter are opaque to btrfs, we just read and write them as a blob for the 134 * higher level verity code. The most common descriptor size is 256 bytes. 135 * 136 * The merkle tree items: 137 * [ inode objectid, BTRFS_VERITY_MERKLE_ITEM_KEY, offset ] 138 * 139 * These also start at offset 0, and correspond to the merkle tree bytes. When 140 * fsverity asks for page 0 of the merkle tree, we pull up one page starting at 141 * offset 0 for this key type. These are also opaque to btrfs, we're blindly 142 * storing whatever fsverity sends down. 143 */ 144 #define BTRFS_VERITY_DESC_ITEM_KEY 36 145 #define BTRFS_VERITY_MERKLE_ITEM_KEY 37 146 147 #define BTRFS_ORPHAN_ITEM_KEY 48 148 /* reserve 2-15 close to the inode for later flexibility */ 149 150 /* 151 * dir items are the name -> inode pointers in a directory. There is one 152 * for every name in a directory. BTRFS_DIR_LOG_ITEM_KEY is no longer used 153 * but it's still defined here for documentation purposes and to help avoid 154 * having its numerical value reused in the future. 155 */ 156 #define BTRFS_DIR_LOG_ITEM_KEY 60 157 #define BTRFS_DIR_LOG_INDEX_KEY 72 158 #define BTRFS_DIR_ITEM_KEY 84 159 #define BTRFS_DIR_INDEX_KEY 96 160 /* 161 * extent data is for file data 162 */ 163 #define BTRFS_EXTENT_DATA_KEY 108 164 165 /* 166 * extent csums are stored in a separate tree and hold csums for 167 * an entire extent on disk. 168 */ 169 #define BTRFS_EXTENT_CSUM_KEY 128 170 171 /* 172 * root items point to tree roots. They are typically in the root 173 * tree used by the super block to find all the other trees 174 */ 175 #define BTRFS_ROOT_ITEM_KEY 132 176 177 /* 178 * root backrefs tie subvols and snapshots to the directory entries that 179 * reference them 180 */ 181 #define BTRFS_ROOT_BACKREF_KEY 144 182 183 /* 184 * root refs make a fast index for listing all of the snapshots and 185 * subvolumes referenced by a given root. They point directly to the 186 * directory item in the root that references the subvol 187 */ 188 #define BTRFS_ROOT_REF_KEY 156 189 190 /* 191 * extent items are in the extent map tree. These record which blocks 192 * are used, and how many references there are to each block 193 */ 194 #define BTRFS_EXTENT_ITEM_KEY 168 195 196 /* 197 * The same as the BTRFS_EXTENT_ITEM_KEY, except it's metadata we already know 198 * the length, so we save the level in key->offset instead of the length. 199 */ 200 #define BTRFS_METADATA_ITEM_KEY 169 201 202 #define BTRFS_TREE_BLOCK_REF_KEY 176 203 204 #define BTRFS_EXTENT_DATA_REF_KEY 178 205 206 #define BTRFS_EXTENT_REF_V0_KEY 180 207 208 #define BTRFS_SHARED_BLOCK_REF_KEY 182 209 210 #define BTRFS_SHARED_DATA_REF_KEY 184 211 212 /* 213 * block groups give us hints into the extent allocation trees. Which 214 * blocks are free etc etc 215 */ 216 #define BTRFS_BLOCK_GROUP_ITEM_KEY 192 217 218 /* 219 * Every block group is represented in the free space tree by a free space info 220 * item, which stores some accounting information. It is keyed on 221 * (block_group_start, FREE_SPACE_INFO, block_group_length). 222 */ 223 #define BTRFS_FREE_SPACE_INFO_KEY 198 224 225 /* 226 * A free space extent tracks an extent of space that is free in a block group. 227 * It is keyed on (start, FREE_SPACE_EXTENT, length). 228 */ 229 #define BTRFS_FREE_SPACE_EXTENT_KEY 199 230 231 /* 232 * When a block group becomes very fragmented, we convert it to use bitmaps 233 * instead of extents. A free space bitmap is keyed on 234 * (start, FREE_SPACE_BITMAP, length); the corresponding item is a bitmap with 235 * (length / sectorsize) bits. 236 */ 237 #define BTRFS_FREE_SPACE_BITMAP_KEY 200 238 239 #define BTRFS_DEV_EXTENT_KEY 204 240 #define BTRFS_DEV_ITEM_KEY 216 241 #define BTRFS_CHUNK_ITEM_KEY 228 242 243 /* 244 * Records the overall state of the qgroups. 245 * There's only one instance of this key present, 246 * (0, BTRFS_QGROUP_STATUS_KEY, 0) 247 */ 248 #define BTRFS_QGROUP_STATUS_KEY 240 249 /* 250 * Records the currently used space of the qgroup. 251 * One key per qgroup, (0, BTRFS_QGROUP_INFO_KEY, qgroupid). 252 */ 253 #define BTRFS_QGROUP_INFO_KEY 242 254 /* 255 * Contains the user configured limits for the qgroup. 256 * One key per qgroup, (0, BTRFS_QGROUP_LIMIT_KEY, qgroupid). 257 */ 258 #define BTRFS_QGROUP_LIMIT_KEY 244 259 /* 260 * Records the child-parent relationship of qgroups. For 261 * each relation, 2 keys are present: 262 * (childid, BTRFS_QGROUP_RELATION_KEY, parentid) 263 * (parentid, BTRFS_QGROUP_RELATION_KEY, childid) 264 */ 265 #define BTRFS_QGROUP_RELATION_KEY 246 266 267 /* 268 * Obsolete name, see BTRFS_TEMPORARY_ITEM_KEY. 269 */ 270 #define BTRFS_BALANCE_ITEM_KEY 248 271 272 /* 273 * The key type for tree items that are stored persistently, but do not need to 274 * exist for extended period of time. The items can exist in any tree. 275 * 276 * [subtype, BTRFS_TEMPORARY_ITEM_KEY, data] 277 * 278 * Existing items: 279 * 280 * - balance status item 281 * (BTRFS_BALANCE_OBJECTID, BTRFS_TEMPORARY_ITEM_KEY, 0) 282 */ 283 #define BTRFS_TEMPORARY_ITEM_KEY 248 284 285 /* 286 * Obsolete name, see BTRFS_PERSISTENT_ITEM_KEY 287 */ 288 #define BTRFS_DEV_STATS_KEY 249 289 290 /* 291 * The key type for tree items that are stored persistently and usually exist 292 * for a long period, eg. filesystem lifetime. The item kinds can be status 293 * information, stats or preference values. The item can exist in any tree. 294 * 295 * [subtype, BTRFS_PERSISTENT_ITEM_KEY, data] 296 * 297 * Existing items: 298 * 299 * - device statistics, store IO stats in the device tree, one key for all 300 * stats 301 * (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0) 302 */ 303 #define BTRFS_PERSISTENT_ITEM_KEY 249 304 305 /* 306 * Persistently stores the device replace state in the device tree. 307 * The key is built like this: (0, BTRFS_DEV_REPLACE_KEY, 0). 308 */ 309 #define BTRFS_DEV_REPLACE_KEY 250 310 311 /* 312 * Stores items that allow to quickly map UUIDs to something else. 313 * These items are part of the filesystem UUID tree. 314 * The key is built like this: 315 * (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits). 316 */ 317 #if BTRFS_UUID_SIZE != 16 318 #error "UUID items require BTRFS_UUID_SIZE == 16!" 319 #endif 320 #define BTRFS_UUID_KEY_SUBVOL 251 /* for UUIDs assigned to subvols */ 321 #define BTRFS_UUID_KEY_RECEIVED_SUBVOL 252 /* for UUIDs assigned to 322 * received subvols */ 323 324 /* 325 * string items are for debugging. They just store a short string of 326 * data in the FS 327 */ 328 #define BTRFS_STRING_ITEM_KEY 253 329 330 /* Maximum metadata block size (nodesize) */ 331 #define BTRFS_MAX_METADATA_BLOCKSIZE 65536 332 333 /* 32 bytes in various csum fields */ 334 #define BTRFS_CSUM_SIZE 32 335 336 /* csum types */ 337 enum btrfs_csum_type { 338 BTRFS_CSUM_TYPE_CRC32 = 0, 339 BTRFS_CSUM_TYPE_XXHASH = 1, 340 BTRFS_CSUM_TYPE_SHA256 = 2, 341 BTRFS_CSUM_TYPE_BLAKE2 = 3, 342 }; 343 344 /* 345 * flags definitions for directory entry item type 346 * 347 * Used by: 348 * struct btrfs_dir_item.type 349 * 350 * Values 0..7 must match common file type values in fs_types.h. 351 */ 352 #define BTRFS_FT_UNKNOWN 0 353 #define BTRFS_FT_REG_FILE 1 354 #define BTRFS_FT_DIR 2 355 #define BTRFS_FT_CHRDEV 3 356 #define BTRFS_FT_BLKDEV 4 357 #define BTRFS_FT_FIFO 5 358 #define BTRFS_FT_SOCK 6 359 #define BTRFS_FT_SYMLINK 7 360 #define BTRFS_FT_XATTR 8 361 #define BTRFS_FT_MAX 9 362 363 /* 364 * The key defines the order in the tree, and so it also defines (optimal) 365 * block layout. 366 * 367 * objectid corresponds to the inode number. 368 * 369 * type tells us things about the object, and is a kind of stream selector. 370 * so for a given inode, keys with type of 1 might refer to the inode data, 371 * type of 2 may point to file data in the btree and type == 3 may point to 372 * extents. 373 * 374 * offset is the starting byte offset for this key in the stream. 375 * 376 * btrfs_disk_key is in disk byte order. struct btrfs_key is always 377 * in cpu native order. Otherwise they are identical and their sizes 378 * should be the same (ie both packed) 379 */ 380 struct btrfs_disk_key { 381 __le64 objectid; 382 __u8 type; 383 __le64 offset; 384 } __attribute__ ((__packed__)); 385 386 struct btrfs_key { 387 __u64 objectid; 388 __u8 type; 389 __u64 offset; 390 } __attribute__ ((__packed__)); 391 392 struct btrfs_dev_item { 393 /* the internal btrfs device id */ 394 __le64 devid; 395 396 /* size of the device */ 397 __le64 total_bytes; 398 399 /* bytes used */ 400 __le64 bytes_used; 401 402 /* optimal io alignment for this device */ 403 __le32 io_align; 404 405 /* optimal io width for this device */ 406 __le32 io_width; 407 408 /* minimal io size for this device */ 409 __le32 sector_size; 410 411 /* type and info about this device */ 412 __le64 type; 413 414 /* expected generation for this device */ 415 __le64 generation; 416 417 /* 418 * starting byte of this partition on the device, 419 * to allow for stripe alignment in the future 420 */ 421 __le64 start_offset; 422 423 /* grouping information for allocation decisions */ 424 __le32 dev_group; 425 426 /* seek speed 0-100 where 100 is fastest */ 427 __u8 seek_speed; 428 429 /* bandwidth 0-100 where 100 is fastest */ 430 __u8 bandwidth; 431 432 /* btrfs generated uuid for this device */ 433 __u8 uuid[BTRFS_UUID_SIZE]; 434 435 /* uuid of FS who owns this device */ 436 __u8 fsid[BTRFS_UUID_SIZE]; 437 } __attribute__ ((__packed__)); 438 439 struct btrfs_stripe { 440 __le64 devid; 441 __le64 offset; 442 __u8 dev_uuid[BTRFS_UUID_SIZE]; 443 } __attribute__ ((__packed__)); 444 445 struct btrfs_chunk { 446 /* size of this chunk in bytes */ 447 __le64 length; 448 449 /* objectid of the root referencing this chunk */ 450 __le64 owner; 451 452 __le64 stripe_len; 453 __le64 type; 454 455 /* optimal io alignment for this chunk */ 456 __le32 io_align; 457 458 /* optimal io width for this chunk */ 459 __le32 io_width; 460 461 /* minimal io size for this chunk */ 462 __le32 sector_size; 463 464 /* 2^16 stripes is quite a lot, a second limit is the size of a single 465 * item in the btree 466 */ 467 __le16 num_stripes; 468 469 /* sub stripes only matter for raid10 */ 470 __le16 sub_stripes; 471 struct btrfs_stripe stripe; 472 /* additional stripes go here */ 473 } __attribute__ ((__packed__)); 474 475 #define BTRFS_FREE_SPACE_EXTENT 1 476 #define BTRFS_FREE_SPACE_BITMAP 2 477 478 struct btrfs_free_space_entry { 479 __le64 offset; 480 __le64 bytes; 481 __u8 type; 482 } __attribute__ ((__packed__)); 483 484 struct btrfs_free_space_header { 485 struct btrfs_disk_key location; 486 __le64 generation; 487 __le64 num_entries; 488 __le64 num_bitmaps; 489 } __attribute__ ((__packed__)); 490 491 #define BTRFS_HEADER_FLAG_WRITTEN (1ULL << 0) 492 #define BTRFS_HEADER_FLAG_RELOC (1ULL << 1) 493 494 /* Super block flags */ 495 /* Errors detected */ 496 #define BTRFS_SUPER_FLAG_ERROR (1ULL << 2) 497 498 #define BTRFS_SUPER_FLAG_SEEDING (1ULL << 32) 499 #define BTRFS_SUPER_FLAG_METADUMP (1ULL << 33) 500 #define BTRFS_SUPER_FLAG_METADUMP_V2 (1ULL << 34) 501 #define BTRFS_SUPER_FLAG_CHANGING_FSID (1ULL << 35) 502 #define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 (1ULL << 36) 503 504 505 /* 506 * items in the extent btree are used to record the objectid of the 507 * owner of the block and the number of references 508 */ 509 510 struct btrfs_extent_item { 511 __le64 refs; 512 __le64 generation; 513 __le64 flags; 514 } __attribute__ ((__packed__)); 515 516 struct btrfs_extent_item_v0 { 517 __le32 refs; 518 } __attribute__ ((__packed__)); 519 520 521 #define BTRFS_EXTENT_FLAG_DATA (1ULL << 0) 522 #define BTRFS_EXTENT_FLAG_TREE_BLOCK (1ULL << 1) 523 524 /* following flags only apply to tree blocks */ 525 526 /* use full backrefs for extent pointers in the block */ 527 #define BTRFS_BLOCK_FLAG_FULL_BACKREF (1ULL << 8) 528 529 /* 530 * this flag is only used internally by scrub and may be changed at any time 531 * it is only declared here to avoid collisions 532 */ 533 #define BTRFS_EXTENT_FLAG_SUPER (1ULL << 48) 534 535 struct btrfs_tree_block_info { 536 struct btrfs_disk_key key; 537 __u8 level; 538 } __attribute__ ((__packed__)); 539 540 struct btrfs_extent_data_ref { 541 __le64 root; 542 __le64 objectid; 543 __le64 offset; 544 __le32 count; 545 } __attribute__ ((__packed__)); 546 547 struct btrfs_shared_data_ref { 548 __le32 count; 549 } __attribute__ ((__packed__)); 550 551 struct btrfs_extent_inline_ref { 552 __u8 type; 553 __le64 offset; 554 } __attribute__ ((__packed__)); 555 556 /* dev extents record free space on individual devices. The owner 557 * field points back to the chunk allocation mapping tree that allocated 558 * the extent. The chunk tree uuid field is a way to double check the owner 559 */ 560 struct btrfs_dev_extent { 561 __le64 chunk_tree; 562 __le64 chunk_objectid; 563 __le64 chunk_offset; 564 __le64 length; 565 __u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; 566 } __attribute__ ((__packed__)); 567 568 struct btrfs_inode_ref { 569 __le64 index; 570 __le16 name_len; 571 /* name goes here */ 572 } __attribute__ ((__packed__)); 573 574 struct btrfs_inode_extref { 575 __le64 parent_objectid; 576 __le64 index; 577 __le16 name_len; 578 __u8 name[0]; 579 /* name goes here */ 580 } __attribute__ ((__packed__)); 581 582 struct btrfs_timespec { 583 __le64 sec; 584 __le32 nsec; 585 } __attribute__ ((__packed__)); 586 587 struct btrfs_inode_item { 588 /* nfs style generation number */ 589 __le64 generation; 590 /* transid that last touched this inode */ 591 __le64 transid; 592 __le64 size; 593 __le64 nbytes; 594 __le64 block_group; 595 __le32 nlink; 596 __le32 uid; 597 __le32 gid; 598 __le32 mode; 599 __le64 rdev; 600 __le64 flags; 601 602 /* modification sequence number for NFS */ 603 __le64 sequence; 604 605 /* 606 * a little future expansion, for more than this we can 607 * just grow the inode item and version it 608 */ 609 __le64 reserved[4]; 610 struct btrfs_timespec atime; 611 struct btrfs_timespec ctime; 612 struct btrfs_timespec mtime; 613 struct btrfs_timespec otime; 614 } __attribute__ ((__packed__)); 615 616 struct btrfs_dir_log_item { 617 __le64 end; 618 } __attribute__ ((__packed__)); 619 620 struct btrfs_dir_item { 621 struct btrfs_disk_key location; 622 __le64 transid; 623 __le16 data_len; 624 __le16 name_len; 625 __u8 type; 626 } __attribute__ ((__packed__)); 627 628 #define BTRFS_ROOT_SUBVOL_RDONLY (1ULL << 0) 629 630 /* 631 * Internal in-memory flag that a subvolume has been marked for deletion but 632 * still visible as a directory 633 */ 634 #define BTRFS_ROOT_SUBVOL_DEAD (1ULL << 48) 635 636 struct btrfs_root_item { 637 struct btrfs_inode_item inode; 638 __le64 generation; 639 __le64 root_dirid; 640 __le64 bytenr; 641 __le64 byte_limit; 642 __le64 bytes_used; 643 __le64 last_snapshot; 644 __le64 flags; 645 __le32 refs; 646 struct btrfs_disk_key drop_progress; 647 __u8 drop_level; 648 __u8 level; 649 650 /* 651 * The following fields appear after subvol_uuids+subvol_times 652 * were introduced. 653 */ 654 655 /* 656 * This generation number is used to test if the new fields are valid 657 * and up to date while reading the root item. Every time the root item 658 * is written out, the "generation" field is copied into this field. If 659 * anyone ever mounted the fs with an older kernel, we will have 660 * mismatching generation values here and thus must invalidate the 661 * new fields. See btrfs_update_root and btrfs_find_last_root for 662 * details. 663 * the offset of generation_v2 is also used as the start for the memset 664 * when invalidating the fields. 665 */ 666 __le64 generation_v2; 667 __u8 uuid[BTRFS_UUID_SIZE]; 668 __u8 parent_uuid[BTRFS_UUID_SIZE]; 669 __u8 received_uuid[BTRFS_UUID_SIZE]; 670 __le64 ctransid; /* updated when an inode changes */ 671 __le64 otransid; /* trans when created */ 672 __le64 stransid; /* trans when sent. non-zero for received subvol */ 673 __le64 rtransid; /* trans when received. non-zero for received subvol */ 674 struct btrfs_timespec ctime; 675 struct btrfs_timespec otime; 676 struct btrfs_timespec stime; 677 struct btrfs_timespec rtime; 678 __le64 reserved[8]; /* for future */ 679 } __attribute__ ((__packed__)); 680 681 /* 682 * Btrfs root item used to be smaller than current size. The old format ends 683 * at where member generation_v2 is. 684 */ 685 static inline __u32 btrfs_legacy_root_item_size(void) 686 { 687 return offsetof(struct btrfs_root_item, generation_v2); 688 } 689 690 /* 691 * this is used for both forward and backward root refs 692 */ 693 struct btrfs_root_ref { 694 __le64 dirid; 695 __le64 sequence; 696 __le16 name_len; 697 } __attribute__ ((__packed__)); 698 699 struct btrfs_disk_balance_args { 700 /* 701 * profiles to operate on, single is denoted by 702 * BTRFS_AVAIL_ALLOC_BIT_SINGLE 703 */ 704 __le64 profiles; 705 706 /* 707 * usage filter 708 * BTRFS_BALANCE_ARGS_USAGE with a single value means '0..N' 709 * BTRFS_BALANCE_ARGS_USAGE_RANGE - range syntax, min..max 710 */ 711 union { 712 __le64 usage; 713 struct { 714 __le32 usage_min; 715 __le32 usage_max; 716 }; 717 }; 718 719 /* devid filter */ 720 __le64 devid; 721 722 /* devid subset filter [pstart..pend) */ 723 __le64 pstart; 724 __le64 pend; 725 726 /* btrfs virtual address space subset filter [vstart..vend) */ 727 __le64 vstart; 728 __le64 vend; 729 730 /* 731 * profile to convert to, single is denoted by 732 * BTRFS_AVAIL_ALLOC_BIT_SINGLE 733 */ 734 __le64 target; 735 736 /* BTRFS_BALANCE_ARGS_* */ 737 __le64 flags; 738 739 /* 740 * BTRFS_BALANCE_ARGS_LIMIT with value 'limit' 741 * BTRFS_BALANCE_ARGS_LIMIT_RANGE - the extend version can use minimum 742 * and maximum 743 */ 744 union { 745 __le64 limit; 746 struct { 747 __le32 limit_min; 748 __le32 limit_max; 749 }; 750 }; 751 752 /* 753 * Process chunks that cross stripes_min..stripes_max devices, 754 * BTRFS_BALANCE_ARGS_STRIPES_RANGE 755 */ 756 __le32 stripes_min; 757 __le32 stripes_max; 758 759 __le64 unused[6]; 760 } __attribute__ ((__packed__)); 761 762 /* 763 * store balance parameters to disk so that balance can be properly 764 * resumed after crash or unmount 765 */ 766 struct btrfs_balance_item { 767 /* BTRFS_BALANCE_* */ 768 __le64 flags; 769 770 struct btrfs_disk_balance_args data; 771 struct btrfs_disk_balance_args meta; 772 struct btrfs_disk_balance_args sys; 773 774 __le64 unused[4]; 775 } __attribute__ ((__packed__)); 776 777 enum { 778 BTRFS_FILE_EXTENT_INLINE = 0, 779 BTRFS_FILE_EXTENT_REG = 1, 780 BTRFS_FILE_EXTENT_PREALLOC = 2, 781 BTRFS_NR_FILE_EXTENT_TYPES = 3, 782 }; 783 784 struct btrfs_file_extent_item { 785 /* 786 * transaction id that created this extent 787 */ 788 __le64 generation; 789 /* 790 * max number of bytes to hold this extent in ram 791 * when we split a compressed extent we can't know how big 792 * each of the resulting pieces will be. So, this is 793 * an upper limit on the size of the extent in ram instead of 794 * an exact limit. 795 */ 796 __le64 ram_bytes; 797 798 /* 799 * 32 bits for the various ways we might encode the data, 800 * including compression and encryption. If any of these 801 * are set to something a given disk format doesn't understand 802 * it is treated like an incompat flag for reading and writing, 803 * but not for stat. 804 */ 805 __u8 compression; 806 __u8 encryption; 807 __le16 other_encoding; /* spare for later use */ 808 809 /* are we inline data or a real extent? */ 810 __u8 type; 811 812 /* 813 * disk space consumed by the extent, checksum blocks are included 814 * in these numbers 815 * 816 * At this offset in the structure, the inline extent data start. 817 */ 818 __le64 disk_bytenr; 819 __le64 disk_num_bytes; 820 /* 821 * the logical offset in file blocks (no csums) 822 * this extent record is for. This allows a file extent to point 823 * into the middle of an existing extent on disk, sharing it 824 * between two snapshots (useful if some bytes in the middle of the 825 * extent have changed 826 */ 827 __le64 offset; 828 /* 829 * the logical number of file blocks (no csums included). This 830 * always reflects the size uncompressed and without encoding. 831 */ 832 __le64 num_bytes; 833 834 } __attribute__ ((__packed__)); 835 836 struct btrfs_csum_item { 837 __u8 csum; 838 } __attribute__ ((__packed__)); 839 840 struct btrfs_dev_stats_item { 841 /* 842 * grow this item struct at the end for future enhancements and keep 843 * the existing values unchanged 844 */ 845 __le64 values[BTRFS_DEV_STAT_VALUES_MAX]; 846 } __attribute__ ((__packed__)); 847 848 #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS 0 849 #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID 1 850 851 struct btrfs_dev_replace_item { 852 /* 853 * grow this item struct at the end for future enhancements and keep 854 * the existing values unchanged 855 */ 856 __le64 src_devid; 857 __le64 cursor_left; 858 __le64 cursor_right; 859 __le64 cont_reading_from_srcdev_mode; 860 861 __le64 replace_state; 862 __le64 time_started; 863 __le64 time_stopped; 864 __le64 num_write_errors; 865 __le64 num_uncorrectable_read_errors; 866 } __attribute__ ((__packed__)); 867 868 /* different types of block groups (and chunks) */ 869 #define BTRFS_BLOCK_GROUP_DATA (1ULL << 0) 870 #define BTRFS_BLOCK_GROUP_SYSTEM (1ULL << 1) 871 #define BTRFS_BLOCK_GROUP_METADATA (1ULL << 2) 872 #define BTRFS_BLOCK_GROUP_RAID0 (1ULL << 3) 873 #define BTRFS_BLOCK_GROUP_RAID1 (1ULL << 4) 874 #define BTRFS_BLOCK_GROUP_DUP (1ULL << 5) 875 #define BTRFS_BLOCK_GROUP_RAID10 (1ULL << 6) 876 #define BTRFS_BLOCK_GROUP_RAID5 (1ULL << 7) 877 #define BTRFS_BLOCK_GROUP_RAID6 (1ULL << 8) 878 #define BTRFS_BLOCK_GROUP_RAID1C3 (1ULL << 9) 879 #define BTRFS_BLOCK_GROUP_RAID1C4 (1ULL << 10) 880 #define BTRFS_BLOCK_GROUP_RESERVED (BTRFS_AVAIL_ALLOC_BIT_SINGLE | \ 881 BTRFS_SPACE_INFO_GLOBAL_RSV) 882 883 enum btrfs_raid_types { 884 BTRFS_RAID_RAID10, 885 BTRFS_RAID_RAID1, 886 BTRFS_RAID_DUP, 887 BTRFS_RAID_RAID0, 888 BTRFS_RAID_SINGLE, 889 BTRFS_RAID_RAID5, 890 BTRFS_RAID_RAID6, 891 BTRFS_RAID_RAID1C3, 892 BTRFS_RAID_RAID1C4, 893 BTRFS_NR_RAID_TYPES 894 }; 895 896 #define BTRFS_BLOCK_GROUP_TYPE_MASK (BTRFS_BLOCK_GROUP_DATA | \ 897 BTRFS_BLOCK_GROUP_SYSTEM | \ 898 BTRFS_BLOCK_GROUP_METADATA) 899 900 #define BTRFS_BLOCK_GROUP_PROFILE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ 901 BTRFS_BLOCK_GROUP_RAID1 | \ 902 BTRFS_BLOCK_GROUP_RAID1C3 | \ 903 BTRFS_BLOCK_GROUP_RAID1C4 | \ 904 BTRFS_BLOCK_GROUP_RAID5 | \ 905 BTRFS_BLOCK_GROUP_RAID6 | \ 906 BTRFS_BLOCK_GROUP_DUP | \ 907 BTRFS_BLOCK_GROUP_RAID10) 908 #define BTRFS_BLOCK_GROUP_RAID56_MASK (BTRFS_BLOCK_GROUP_RAID5 | \ 909 BTRFS_BLOCK_GROUP_RAID6) 910 911 #define BTRFS_BLOCK_GROUP_RAID1_MASK (BTRFS_BLOCK_GROUP_RAID1 | \ 912 BTRFS_BLOCK_GROUP_RAID1C3 | \ 913 BTRFS_BLOCK_GROUP_RAID1C4) 914 915 /* 916 * We need a bit for restriper to be able to tell when chunks of type 917 * SINGLE are available. This "extended" profile format is used in 918 * fs_info->avail_*_alloc_bits (in-memory) and balance item fields 919 * (on-disk). The corresponding on-disk bit in chunk.type is reserved 920 * to avoid remappings between two formats in future. 921 */ 922 #define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1ULL << 48) 923 924 /* 925 * A fake block group type that is used to communicate global block reserve 926 * size to userspace via the SPACE_INFO ioctl. 927 */ 928 #define BTRFS_SPACE_INFO_GLOBAL_RSV (1ULL << 49) 929 930 #define BTRFS_EXTENDED_PROFILE_MASK (BTRFS_BLOCK_GROUP_PROFILE_MASK | \ 931 BTRFS_AVAIL_ALLOC_BIT_SINGLE) 932 933 static inline __u64 chunk_to_extended(__u64 flags) 934 { 935 if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0) 936 flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE; 937 938 return flags; 939 } 940 static inline __u64 extended_to_chunk(__u64 flags) 941 { 942 return flags & ~BTRFS_AVAIL_ALLOC_BIT_SINGLE; 943 } 944 945 struct btrfs_block_group_item { 946 __le64 used; 947 __le64 chunk_objectid; 948 __le64 flags; 949 } __attribute__ ((__packed__)); 950 951 struct btrfs_free_space_info { 952 __le32 extent_count; 953 __le32 flags; 954 } __attribute__ ((__packed__)); 955 956 #define BTRFS_FREE_SPACE_USING_BITMAPS (1ULL << 0) 957 958 #define BTRFS_QGROUP_LEVEL_SHIFT 48 959 static inline __u16 btrfs_qgroup_level(__u64 qgroupid) 960 { 961 return (__u16)(qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT); 962 } 963 964 /* 965 * is subvolume quota turned on? 966 */ 967 #define BTRFS_QGROUP_STATUS_FLAG_ON (1ULL << 0) 968 /* 969 * RESCAN is set during the initialization phase 970 */ 971 #define BTRFS_QGROUP_STATUS_FLAG_RESCAN (1ULL << 1) 972 /* 973 * Some qgroup entries are known to be out of date, 974 * either because the configuration has changed in a way that 975 * makes a rescan necessary, or because the fs has been mounted 976 * with a non-qgroup-aware version. 977 * Turning qouta off and on again makes it inconsistent, too. 978 */ 979 #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT (1ULL << 2) 980 981 #define BTRFS_QGROUP_STATUS_VERSION 1 982 983 struct btrfs_qgroup_status_item { 984 __le64 version; 985 /* 986 * the generation is updated during every commit. As older 987 * versions of btrfs are not aware of qgroups, it will be 988 * possible to detect inconsistencies by checking the 989 * generation on mount time 990 */ 991 __le64 generation; 992 993 /* flag definitions see above */ 994 __le64 flags; 995 996 /* 997 * only used during scanning to record the progress 998 * of the scan. It contains a logical address 999 */ 1000 __le64 rescan; 1001 } __attribute__ ((__packed__)); 1002 1003 struct btrfs_qgroup_info_item { 1004 __le64 generation; 1005 __le64 rfer; 1006 __le64 rfer_cmpr; 1007 __le64 excl; 1008 __le64 excl_cmpr; 1009 } __attribute__ ((__packed__)); 1010 1011 struct btrfs_qgroup_limit_item { 1012 /* 1013 * only updated when any of the other values change 1014 */ 1015 __le64 flags; 1016 __le64 max_rfer; 1017 __le64 max_excl; 1018 __le64 rsv_rfer; 1019 __le64 rsv_excl; 1020 } __attribute__ ((__packed__)); 1021 1022 struct btrfs_verity_descriptor_item { 1023 /* Size of the verity descriptor in bytes */ 1024 __le64 size; 1025 /* 1026 * When we implement support for fscrypt, we will need to encrypt the 1027 * Merkle tree for encrypted verity files. These 128 bits are for the 1028 * eventual storage of an fscrypt initialization vector. 1029 */ 1030 __le64 reserved[2]; 1031 __u8 encryption; 1032 } __attribute__ ((__packed__)); 1033 1034 #endif /* _BTRFS_CTREE_H_ */ 1035